This invention relates generally to a power combining mechanism and more particularly to a hydro-mechanical power combining mechanism and its use.
Power combining mechanisms are generally known in the art. Some are referred to as split torque mechanisms and function to combine the energies of a hydrostatic fluid unit in combination with a summing planetary gear arrangement. Even though these are effective units, they are many times more bulky and complex units, thus more costly. In order to reduce the cost, another known concept eliminates the summing planetary gear arrangement and rotates the entire fluid motor unit. In this arrangement, an external source of pressurized fluid is used to cause one portion of the fluid motor to proportionally rotate relative to the other portion of the fluid motor. This known concept, set forth in U.S. Pat. No. 5,396,768 issued on Mar. 14, 1995 to Joshua Zulu, creates other challenges, such as the rotating outer housing, the valving of pressurized fluid into the fluid motor, and keeping all of the components in true alignment with one another.
The subject invention is directed to overcome one or more of the problems set forth above.
In one aspect of the present invention a power combining device comprises first and second rotatable input/output members, first and second end members, a valving plate, a camplate, a rotating barrel, a plurality of piston assemblies, a drive sleeve and a cover member. The first and second rotatable input/output members are disposed in longitudinal alignment with one another and defines a reference axis extending longitudinally through both the first and second rotatable input/output members. The first end member has a face surface, first and second inlet/outlet ports communicating with the face surface, and a shaft bearing bore defined therethrough. The first input/output member is disposed within the shaft bearing bore of the first end member. The valving plate has first and second opposed faces with the first opposed face being in mating contact with the face surface of the first end member. The valving plate is disposed about the first input/output member and drivingly connected thereto. The second end member has a shaft bearing bore defined therethrough and the second input/output member is disposed in the shaft bearing bore of the second end member. The camplate has a reference plane defined therein perpendicular to the reference axis and a cam surface thereon disposed at an acute angle with respect to the reference plane. The camplate is disposed about the second input/output member and is located adjacent to the second end member. The rotating barrel has first and second end faces, a plurality of piston bores defined therein about the reference axis and each piston bore of the plurality of piston bores extend inward from the second end face generally along the reference axis and each bore communicates with the first end face thereof. The rotating barrel is disposed about and in driving engagement with the second input/output member. The plurality of piston assemblies slideably is disposed within the plurality of piston bores in the rotating barrel and defines a plurality of pressure chambers therebetween. The plurality of pistons is in mating contact with the cam surface of the camplate. The drive sleeve is disposed about the valving plate, the rotating barrel, the plurality of pistons, and the camplate and the drive sleeve is drivingly connected to the valving plate and the camplate. The cover member extends between and is sealingly connected to the first and second end members.